Experts say a 10 to 20 minute “power nap” is best for refreshing your mind and increasing energy and alertness. You don't go into a deep sleep so you are able to wake right up without being drowsy.
A 30 minute nap can lead to 30 minutes of grogginess. Trust, I have experienced this! You’ll experience some of that same cloudiness if you sleep for an hour, but 60 minute naps are good for memory boosting.
The longest naps—around 90 minutes—are good for those people who just don’t get enough sleep at night. It’s a complete sleep cycle and can improve emotional memory and creativity.
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